On an upcoming episode of NBC's RUNNING WILD WITH BEAR GRYLLS, world-renowned survivalist Bear Grylls ("Get Out Alive with Bear Grylls," "Man vs. Wild") leads Zac Efron ("Neighbors") on a non-stop extreme survival journey into the Northeast Appalachian mountain range wilderness. With Bear's help, Zac challenges himself physically as well as mentally on an awe-inspiring journey he could never have imagined.

The series airs Mondays on NBC (8-9 p.m. ET) on NBC. Get a sneak peek below!

In this hour-long alternative series, "Running Wild with Bear Grylls," the famed adventurer and survivalist will take six celebrities into the most remote and wild locations in the U.S. and around the world for a 48-hour journey of a lifetime.

Each of the celebrities endure the harsh wilderness in high-octane, action-based and empowering journeys spread over six remote locations. From skydiving into the Catskill Mountains, to repelling down the cliffs of Utah and battling torrential wind and rain in Scotland, Grylls and each celebrity will have to push both their minds and bodies to the limit to successfully complete their journey.

The show was created by Grylls, who recently starred on the NBC series "Get Out Alive with Bear Grylls."